Modular roofing assemblies are increasingly applied for the protection of buildings or other load-bearing structures, for both residential and industrial use, which assemblies are made of metal sheets having specially profiled edges, and are either pre-assembled or directly mounted to the roofing.
These particular roofing systems have a much lighter weight than conventional solutions, and further assure enhanced universal use.
The connection to the load-bearing structure of the roof is usually obtained by directly attaching the metal sheets to the structure, typically by perforation and/or punching. Furthermore, these sheets are interconnected by placing adjacent sheets in such a manner to provide an overlap relationship between their edges.
As an alternative to the above, the sheets are secured in adjacent positions to brackets, which are in turn fastened to the underlying structure, whereupon the adjacent edges are crimped together by means of special tools.
As is apparent, these conventional solutions have the drawback of requiring a somewhat laborious assembly process, and of requiring the performance of complex operations, using particular tools. Furthermore, the anchorage holes in the sheets are weak points, possibly giving rise to cracks or metal weakening areas, as well as permeable points for the whole structure. Therefore, these structures are excessively vulnerable to weather conditions, particularly rain, in case of possibly imperfect connections, and wind, especially in cantilever roofing assemblies.
In an attempt to obviate the above drawbacks, several solutions have been proposed in which the roofing assembly is connected to the bearing structure by intermediate fastening means, which are anchored to the some structure.
Particularly, from EP-0964114, in the name of the same applicant, a sheet metal roofing structure is known, which comprises metal sheets whose non-adjacent longitudinal edges are suitably shaped with a predetermined profile.
The anchorage of the sheets to the roof of the building is accomplished by means of supporting blocks, which have been previously mounted to the structure, and have alternating projections and recesses, to define a profile that is complementary to the sheet edges. This allows the sheets to be joined together by partial overlapping of their edges and snap fit in anchor blocks.
This arrangement allows anchorage and quick overlapping connection of adjacent metal sheets by exerting a downward force that allows such sheets to slide in the connection seats defined by the alternating projections and recesses of the blocks.
Moreover, from EP-A-0124707 is known a roof structure having all the features of the preamble of the main claim 1.
While these arrangements provide an easy-to-mount covering assembly, having excellent characteristics of load and weather resistance and impermeability, it still has a few drawbacks and is susceptible to improvements.